One of the important applications for business-to-business electronic commerce is in procurement and inventory management using electronic data interchange(EDI). Using online catalogs and approved supplier lists, firms can easily create requisitions and purchasing documents. The emerging trend in EDI technology is changed from VAN(Value Added Network) based EDI to XML based EDI. This paper intends to suggest a component-based XML/EDI system using Unified Modeling Language(UML), as an application system for automobile part industry. Applying component based XML/EDI systems designed with UML methodology, we analyzed the workflow and the document on procurement process between trading partners and implemented a prototype of efficient XML/EDI system, as a surrogate of existing VAN/EDI. The result of applying object-oriented CBD(Component Based Development) technique is to minimize the risk of life cycle and facilitate the reuse of software as mentioned to limitation of information engineering methodology. It enables the interoperability with corporate legacy systems such as ERP(Enterprise Resource Planning), SCM(Supply Chain Management). This system proposes a solution to apply analysis phase and design phase in implementation of XML/EDI system. The implementation of XML/EDI system using CBD shows the ease of use in software reuse and the interoperability with corporate internal information system. The purchasing department with XML/EDI system can electronically communicate purchase orders, delivery schedules to external suppliers and interoperate with other application systems.